Past that, and it might be a silly one, but you're positive that the report in question only has a custom table resource right? Also, can you run the report in the SolarWinds website directly and then export to CSV/Excel from there?
If you have looked through all of the steps in that KB, I think the next helpful bit for this thread would be a screenshot of the actual report in the SolarWinds website.
Loop1 Systems: SolarWinds Training and Professional Services
That might be the issue. I do not think that the old win32 app Report Writer reports can actually be exported to CSV or Excel.
I would remake that report using the web report writer and see if that resolved the issue.
You might be able to update your URL as well, I haven't tried this in years so I can't promise it wil work: How to Export NPM Report Writer Data to Excel (xls or csv)???
Basically you just append
to the end of your report URL.
I have an update and I was looking at the wrong report before. The report IS web based.
Appending &dataformat=xls to the end of the url does not change the display when I copy/past the url with or with out the data formatting option. I am still required to then click to export as excel or click to export as pdf. Below is the Custom Table.
If it's a web-based report; then you do not need to use the addition to the end of the URL.
If you are now able to export to excel after running the report in the website and then clicking the "export to excel" option; then the export functionality is definitely working.
At this point, if you are still not able to see the excel attachments, then I would suggest opening a ticket with SolarWinds tech support to have an investigation in the logs to see if there is an observable error.
I would probably ping your email admin as well and make sure that the emails aren't being stripped of attachments due to a security policy.